Vim indent xml file

I like Berei's answer. However, I think the following is a little more flexible in that you don't have to alter your vimrc file. Plus it is easier to format select portions of the XML file (something I happen to do a lot).

First, highlight the XML you want to format.

Then, in visual mode, type ! xmllint --format -

Your command-line at the bottom will look like this:

:'<,'>!xmllint --format -

Then hit enter.

Technical Explanation

The selected text is sent to the xmllint command, then --format'ed, and the results of xmllint are placed over your selected text in vim. The - at the end of the command is for receiving standard input - which, in this case, is the selected text that vim sends to xmllint.

A simple solution that I like which doesn't require any 3rd party tool is to insert a newline before each opening tag '<...>'. Then you can use standard vim auto-indentation. In short:

1. %s/</\r</g
2. gg=G to auto indent

Use an external program to indent your xml files. In this case I've choosen xmllint, so set the command to the equalprg option:

:set equalprg=xmllint\ --format\ -

Now you can execute

gg=G

to let xmllint format your xml files.

To get it every time you use vim, use an autocommand to set it.

autocommand from a comment below

au FileType xml setlocal equalprg=xmllint\ --format\ --recover\ -\ 2>/dev/null